I prayed behind an imam and did not recite Surat al-Fatihah because of his speed. When he finished, I performed a rak'ah. Is my action valid?

Question:
He says: Honorable Shaykh, may Allah grant you success. He says: I prayed with an imam, and in the third rak'ah he recited Surat al-Fatihah hastily, to a degree that I was unable to, I was unable to recite it with him. So when he finished the prayer, I stood up and performed another rak'ah, then I said the taslim.

Answer:
This is a mistake. The imam's recitation is sufficient if you are unable to recite; you are excused, my brother. If you are unable to recite Surat al-Fatihah behind the imam, you are excused, and the recitation is dropped from you, and the imam's recitation is sufficient. And praise be to Allah. Yes, we return to emphasize the issue of what is with the one who differs from you of truth or correctness. We say: You are in three states, pay attention. Perform.
You are in three states. Either you say he has no truth at all, and everything he has is wrong; this is not permissible. The second state is that you say he was correct in such-and-such and wrong in such-and-such, and this is justice. The third state is that you clarify the error and remain silent; you do not say he has no error and no correctness, you only clarify the error and remain silent. This is acceptable, but it is less than the one who clarifies and explains.